Showing posts with label printf(). Show all posts
Showing posts with label printf(). Show all posts

First C Program

Your First C Program

Here, is a Hello World program in C
#include<stdio.h> //Pre-processor directive
void main()  //main function declaration
{
printf("Hello World"); //to output the string on a display
getch ();  //terminating function
}
Here is the code explanation:

Pre-processor directive

#include is a pre-processor directive in 'C.'
#include <stdio.h>, stdio is the library where the function printf is defined. printf is used for generating output. Before using this function, we have to first include the required file, also known as a header file (.h).
You can also create your own functions, group them in header files and declare them at the top of the program to use them. To include a file in a program, use pre-processor directive
#include <file-name>.h
File-name is the name of a file in which the functions are stored. Pre-processor directives are always placed at the beginning of the program.

The main function

The main function is a part of every 'C' program. We can represent the main function in various forms, such as:
  • main()
  • int main()
  • void main()
  • main(void)
  • void main(void)
  • int main(void)
The empty parentheses indicate that this function does not take any argument, value or a parameter. You can also represent this explicitly by placing the keyword void inside the parentheses. The keyword void means the function does not return any value, in this case, the last statement is always getch ().
#include<stdio.h> //Pre-processor directive
int main()  //main function declaration
{
printf("Hello World"); //to output the string on a display
return 0;  //terminating function
}
In the above example, the keyword int means the function will return an integer value. In this case, the last statement should always return 0.

The source code

After the main function has been declared, we have to specify the opening and closing parentheses. Curly brackets { }, indicate the starting and end of a program. These brackets must be always put after the main function. All the program code is written inside these brackets, such as declarative and executable part.
The printf function generates the output by passing the text "Hello World!"
The semicolon ; determines the end of the statement. In C, each statement must end with a semicolon.
So we have successfully installed the compiler and now can begin working in 'C.' We will write a simple program that will say hello to us. Let's start.

How to run C Program

Step 1) Create a new Project
Step 2) In the pop-up,
  1. Select File
  2. Choose the "C/C++ Source"
  3. Click "Go."
Step 3) Continue, by clicking on "Next."
Step 4) To create the new file ,select a "C" file then click on "Next" button to continue.
Step 5) Set the file path by clicking the "..." button, the explorer window permits to create the C file.
Step 6) Select the path of your new C File then its name which has .c extension and save it.
Step 7) Finally, to confirm the C file creation click "Finish."
Step 8) Enter the code, save it and compile it by clicking on the "Build & Run "button.
Here is the result:
 Hello, World! 

Summary

  • The main function is a mandatory part of every 'C' program.
  • To use the functionality of a header file, we have to include the file at the beginning of our program.
  • Every 'C' program follows a basic structure.

Count number of students above,below and average students

Count no. of students above,below and average students

  #include<stdio.h>
  #include<conio.h>
   void main()
    {
     int a[10];
     int aa=0,ba=0,ae=0,i;
     clrscr();
     printf("Enter the marks:\n");
     for(i=0;i<10;i++)
       {
scanf("%d",&a[i]);
if(a[i]>55)
aa++;
else if(a[i]<55)
ba++;
else
ae++;
       }
     printf("No. OF AVG STUDENTS ARE:%d\n",ae);
     printf("No. OF ABOVE AVERAGE STUDENTS:%d\n",aa);
     printf("No. OF BELOW AVERAGE STUDENTS ARE:%d",ba);
    getch();
   }

constants usage in C

Basic example showing constants usage in C

#include
/*constants for bonus rates and sales*/
#define BONUSRATE1 0.1
#define BONUSRATE2 0.15
#define BONUSRATE3 0.2
#define SALES1 2000
#define SALES2 5000
#define SALES3 10000
int main()
{
int sales;
double commission;
/*get employees sales*/
printf("Please enter your total sales to the nearest dollar.\n");
scanf("%d", &sales);
/*calculate employees bonus based on info*/
if(sales <=2000)
{
commission = sales * BONUSRATE1;
printf("%g\n" , commission);
}
else if(sales > 2000 && sales <=5000)
{
commission = sales * BONUSRATE2;
printf("%g\n" , commission);
}
else
{
commission = sales * BONUSRATE3;
printf("%g\n" , commission);
}

return 0;
}

a demo program which represent the ATM transaction

ATM programing

ATM C programing language Program code

 ‎/*Note Pin code is 1234*/
#include<stdio.h>
#include<conio.h>

void main(void)
{ unsigned long amount=1000,deposit,withdr​aw;
int choice,pin=0,k=0;
char another='y';

while(pin!=1234)
{ clrscr();
gotoxy(30,25);
printf("Enter pin:");
scanf("%d",&pin);
}
clrscr();
do
{

printf("********Welcome to ATM Service**************\n");
printf("1. Check Balance\n");
printf("2. Withdraw Cash\n");
printf("3. Deposit Cash\n");
printf("4. Quit\n");
printf("******************​**************************​*\n\n");
printf("Enter your choice: ");
scanf("%d",&choice);
switch(choice)
{
case 1:
printf("\nYour Balance is Rs : %lu ",amount);
break;
case 2:
printf("\nEnter the amount to withdraw: ");
scanf("%lu",&withdraw);
if(withdraw%100!=0)
{
printf("\nPlease enter

amount in multiples of 100");
}else if(withdraw>(amount-500))
{

printf("\nInsufficient Funds");
}else
{

amount=amount-withdraw;

printf("\n\nPlease collect cash");

printf("\nYour balance is %lu",amount);
}
break;
case 3:
printf("\nEnter amount to deposit");
scanf("%lu",&deposit);
amount=amount+deposit;
printf("Your balance is %lu",amount);
break;
case 4:
printf("\nThank you for using ATM");
break;
default:
printf("\nInvalid Choice");
}
printf("\n\n\nDo you want another transaction?(y/n): ");
fflush(stdin);
scanf("%c",&another);
if(another=='n'||another==​'N')
k=1;
}while(!k);
printf("\n\nHave a nice day");
getch();

}

Descending an array using c programming

ARRANGE THE ELEMENTS IN ARRAY IN DESCENDING ORDER

main()
{
int a[100],i,n,j,search,temp;
printf("\n how many no's in array");
scanf("%d",&n);
printf("\n enter %d elements in array",n);
for(i=0;i
scanf("%d",&a[i]);
for(i=0;i
{
for(j=i+1;j
{
if(a[i]
{
temp=a[i];
a[i]=a[j];
a[j]=temp;
}
}
printf("%4d",a[i]);
}
getch();
}

add two numbers without using operator as like +

Add Two numbers without using operator


#include<stdio.h>
int main(){
  
    int a,b;
    int sum;
    printf("Enter any two integers: ");
    scanf("%d%d",&a,&b);
    //sum = a - (-b);
    sum = a - ~b -1;
    printf("Sum of two integers: %d",sum);
    return 0;
}

Add two matrices and store the result into another matrice

Add two matrices and store the result

#include<stdio.h>
#include<conio.h>
void main()
{
int a[3][3],b[3][3],c[3][3],i,j;
clrscr();
printf("Enter the elements into matrix A\n");
for(i=0;i<3;i++)
for(j=0;j<3;j++)
scanf("%d",&a[i][j]);
printf("\nEnter the elements into matrix B\n");
for(i=0;i<3;i++)
for(j=0;j<3;j++)
scanf("%d",&b[i][j]);
for(i=0;i<3;i++)
for(j=0;j<3;j++)
c[i][j]=a[i][j]+b[i][j];
for(i=0;i<3;i++)
{
printf("\t\t");
for(j=0;j<3;j++)
printf("%d\t",c[i][j]);
printf("\n\a");
}


getch();
}

use of pointer with array to do a sum


Add Pointers

#include<stdio.h>
#include<conio.h>
 void main()
 {
 int a[10],sum=0;
 int *j;
 int i,n;
 clrscr();
 printf("Enter how many elements u want to add:");
 scanf("%d",&n);
 printf("Enter the elements:");
 for(i=0;i<n;i++)
 {
 scanf("%d",&a[i]);
 }
  j=&a[0];
 for(i=0;i<n;i++)
     {


       sum=sum+*j;
       j++;
     }
 printf("sum=%d",sum);
}

Add numbers using command line arguments (CLA)

Add numbers using command line arguments (CLA)

#include<stdio.h>
#include<conio.h>
#include<stdlib.h>

void main(int argc,char *argv[])
{
int sum=0,i;
//Compare if proper number of arguments have been entered
if(argc<3)

{
printf("Insufficient number of arguments:\n");
getch();
return 0;
}

//Add all the numbers entered using atoi function
for(i=1;i<argc;i++)
{
sum+=atoi(argv[i]);
}

//print the sum
printf("Ans=%d",sum);
getch();
}

bubble sort using user defined function

A bubble sort routine

# include
# include
void bubblesort(int array[],int size);
void main()
{
int values[10],j;
for(j=0;j<10;j++)
values[j] = rand()%100;
/*unsorted*/
printf("\nUnsorted values.\n");
for(j=0;j<10;j++)
printf("%d ",values[j]);
/*sorted*/
printf("\nSorted values.\n");
bubblesort(values,10);
for(j=0;j<10;j++)
printf("%d ",values[j]);
}
void bubblesort(int array[],int size)
{
int tmp ,i,j;
for(i = 0;i
for(j=0;j < size;j++)
if(array[i] < array[j])
{
tmp = array[i];
array[i] = array[j];
array[j] = tmp;
}
}